1. Mechanical Design & IP Rating: The VGS is an enclosed unit with a metal case, which provides physical protection, enhanced heat dissipation, and inherent EMI suppression. The VOF is an open-frame design, lacking an enclosure and thus relying entirely on the host system for cooling and shielding. Post-replacement, the system-level EMI compliance and cooling airflow design must be re-evaluated. 2. Safety Isolation Voltage: The VGS is rated for 4kV isolation, compared to 3kV for the VOF. This higher rating allows the VGS to withstand greater transient voltage spikes between input and output, offering superior robustness in harsh industrial environments prone to lightning surges or where stringent safety standards apply. 3. Thermal Performance & Power Density: The VOF offers slightly higher output power (80W vs. 75W) in a smaller form factor, resulting in a significantly higher power density. Although its maximum operating temperature is 10°C higher (80°C), its open-frame construction makes heat dissipation more dependent on external conditions. Post-replacement, it is critical to verify the actual temperature rise within the target chassis to ensure operation remains within the required derating curve. 4. Critical Electrical Specifications: Input Voltage Lower Limit: The VOF's minimum AC input is 90VAC, higher than the VGS's 85VAC. In areas with extremely unstable line voltage, the VGS may offer better low-voltage startup/hold-up capability. Features: The VGS features an adjustable output, facilitating field tuning. The VOF offers DC input capability, emphasizing compatibility with DC power sources. If the original design relies on output voltage adjustability, the substitution is not viable.